Conventional portable electronic products are designed to be relatively light, thin, and small so that they can be easily carried by users. Such a portable electronic product generally displays a pattern by means of a pattern displaying device, which reflects a directional light source via a reflective structure to display a predetermined pattern.
Taiwanese Patent No. 1427341 discloses a displaying device including a plurality of light guide plates that are stacked together and that have reflective portions, and a plurality of light sources that correspondingly cooperate with the light guide plates. Each of the light plates has a plurality of reflective portions that constitute predetermined patterns, so that different patterns can be respectively displayed by different light guide plates by means of lighting different light sources. However, the displaying device may show different patterns by simultaneously using a plurality of light guide plates, resulting in a more complicated structure that occupies more space within the electronic product. In addition, adoption of multiple light guide plates requires higher manufacturing costs of the electronic product.
On the other hand, Taiwanese Patent No. 1283779 discloses a pattern displaying device that includes a light guide plate and two light sources. The light guide plate is formed with two sets of triangular cavities. When the two light sources are simultaneously illuminated, the light guide plate may display a predetermined pattern. Such a pattern displaying device is monotonous and has less variety in terms of operation and use.